12-1-101 Description: This Rule limits the emission of total reduced sulfur (TRS) from operations at kraft pulp
mills. Meeting the limitations of this Rule shall not exempt the operation of a kraft pulp mill from other requirements
of the District or California law.(Amended July 16, 1980)

12-1-102 Exemptions: The APCO will not consider periods of excess emissions reported under subsection 121402.1
to be indicative of a violation provided that:

102.1 The TRS emissions do not exceed the allowable limits from recovery furnaces more than 1% of the total
number of continuous 12hour periods of operation possible in any calendar quarter, (excluding periods of shutdown,
startup or malfunctions and periods when the facility is not operating), and

102.2 The APCO determines that the affected facility, including air pollution control equipment, is maintained
and operating in a manner which is consistent with good air pollution control practice for minimizing emissions
during periods of excess emissions. (Added July 16, 1980)

12-1-200 DEFINITIONS

12-1-201 Digester System: Each continuous digester or each batch digester used for cooking of wood in white
liquor, and associated chip steamer(s) below tank(s), flash tanks(s) and condenser(s).(Added July 16, 1980)

12-1-202 Kraft Pulp Mill: Any stationary source which produces pulp from wood by cooking (digesting) wood chips
in a water solution of sodium hydroxide and sodium sulfide (white liquor) at high temperature and pressure. Regeneration
of the cooking chemicals through a recovery process is considered part of the kraft pulp mill. (Amended July 16,
1980)

12-1-204 Lime Kiln: A unit used to calcine lime mud, which consists primarily of calcium carbonate, into quick
lime which is calcium oxide. (Added July 16, 1980)

12-1-205 Multiple Effect Evaporator System: The multipleeffect evaporator(s) and associated condenser(s) and hotwell(s)
used to concentrate the spent cooking liquid (black liquor) that is separated from the pulp.(Added July 16, 1980)

12-1-206 Smelt Dissolving Tank: A vessel used for dissolving the smelt collected from the recovery furnace. (Added
July 16, 1980)

12-1-301 Discharge From Kraft Recovery Furnaces: A person shall not discharge from any kraft recovery furnace
TRS in amounts exceeding 15 ppm (dry) as an average over the hours of operation in any operating day, or in amounts
exceeding 40 ppm (dry) for more than 60 cumulative minutes in any operating day; or from all kraft recovery furnaces
TRS in amounts exceeding 150 g per metric ton (0.3 lbs. per ton) of air dried, unbleached kraft pulp produced during
an operating day.

12-1-303 Discharges From Lime Kilns: A person shall not discharge from any lime kiln TRS in amounts exceeding 40
ppm (dry) averaged over any period of 50 consecutive minutes in any operating day; or TRS in amounts exceeding
75 g per metric ton (.15 lbs. per ton) of airdried unbleached kraft pulp produced during an operating day.

12-1-304 Discharges From Digester Systems and Multiple Effect Evaporator Systems: A person shall not discharge
from any digester system or multiple effect evaporator system TRS in excess of 5 ppm on a dry basis, averaged over
a 12 hour period, unless the following conditions are met:

304.1 The gases are combusted in a lime kiln subject to the provisions of Section 121303 of this rule. (Added
July 16, 1980)

12-1-305 Discharges From Other Sources: A person shall not discharge from any sources other than those specified
in Sections 121301 through 121304 TRS exceeding 15 ppm (dry) averaged over a period of 30 consecutive minutes (Amended
July 16, 1980)

12-1-400 ADMINISTRATIVE REQUIREMENTS

12-1-401 Schedule of Compliance for Lime Kilns:

401.1 By January 1, 1981, submit to the APCO a final control plan describing the steps and time schedule to
be followed to achieve compliance with subsection 121301.1

401.2 By July 1, 1981, submit an application to the APCO for authority to construct.

401.3 By January 1, 1983, complete onsite construction or installation of emission control equipment.

401.4 By July 1, 1983, be in final compliance with subsection 121302.1. (Added July 16, 1980)

12-1-402 Reports of Excessive Emissions: For the purpose of reports required, the procedure will be as follows:

402.2 Emissions From Lime Kilns: All 60 minute periods during which TRS concentrations exceed 40 ppm, and all
periods during which TRS emissions exceed 0.15 lbs. per ton of pulp produced. After July 1, 1983, only TRS concentrations
which exceed 20 ppm averaged over an operating day will be reported. (Added July 16, 1980)

12-1-500 MONITORING AND RECORDS

12-1-501 Monitoring: The person responsible for emissions from any kraft pulp mill shall provide, install, maintain
and continuously operate analytical instruments approved by the APCO to monitor TRS emissions from each kraft recovery
furnace and each lime kiln.

12-1-502 Record Maintenance for Two Years: Monitoring records of the equipment required by Section 121501 shall
be kept for a period of two years and shall be made available to the APCO upon request. (Added July 16, 1980)

12-1-503 Monthly Summary: The persons responsible for emissions being monitored pursuant to Section 121501 shall
provide in such form as prescribed by the APCO a summary of data obtained during each calendar month, as specified
in the Manual of Procedures (Added July 16, 1980)

12-1-600 MANUAL OF PROCEDURES

12-1-601 Testing: Emissions shall be tested according to methods outlined in the Manual of Procedures(Added
July 16, 1980)